Question: The midpoint of a line segment is located at $(1, -2)$. If one of the endpoints is $(4, 5)$, what is the other endpoint? Express your answer as an ordered pair.
The $x$-coordinate and $y$-coordinate of the midpoint are the averages of the $x$-coordinates and $y$-coordinates of the endpoints, respectively.  Since $4-3=1$, the $x$-coordinate of the other endpoint is $1-3=-2$.  Since $5-7=-2$, the $y$-coordinate of the other endpoint is $-2-7=-9$.  Therefore, the endpoints are $(4,5)$ and $\boxed{(-2,-9)}$.